Vat dye and process of making same.



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UNITED STATES PATENT OFF-ICE.

ALBRECHT SCHMIDTAND ERNST BRYK, or noorrs'r-oN-Tnn- AIN, GERMANY,assistionsiro rnntwnnxn VORM. MEISTER, uorus & BRI'TNING, or nocnsr-onrnn- MAIN, QEBMAIiY, A CORPORATION OF GERMANY.

: To (ZZZ whom it mag "concern:

' animal fiber, in the hydrosulfiteva-t, violet,v

whereby the temperature rises to about 80.v

Be it known that We, ALBRno rSoHiu'mT, Ph. 1)., and ERNST BRYK, Ph. I).,citizens of the Empires of Germany and Austria-Hum gary, respectively,residing at Hochst-ontheMain, Germany, have invented certain l new anduseful Improvements in the Manufacturefof ,V at Dyestuffs, of which thefolgrayish-violet to blackish tints, the nitrogroups being reduced inthe vat.

Instead of reducing the nitro-group in the vat, the nitration productsobtained may be' treatedwith reducing. agents, for instance with Na s,Na,S,, zinc and the like, by Which the nitro-group is converted into theamino-group, and the amino-bodies isolated as such. These amino-bodiesare also valuable vat-dyestuttswhich dye on the fiber violet,grayish-violet to blackish tints, Moreover the above mentioned nitroasWell as amino-products are capable of being halogenized and in this casethey can be transformed into fast and useful vat-dyestufi's of similarproperties. The following examples illustrate the processabove referredto, but-the conditions 1111-.

'der which the tests are made may be varied.

Example I: 15 of thioindigo are dis solved in 150 gr. of sulfuric acidmonohydrate; this solution is heated and then 12 gr. of potassiumnitrate are gradually added During this operation thegreen color firstturns blue and finally 'violefired. The mass" is stirred for some time,poured on'ice, filtered and washed with hot water and a diluted solutionof sodium carbonate; in this manner the nit-rated thioindigo isobtained.

I Specification of Letters Patent.

Application filed August 14, 1909. Serial No. 512,810.

VAT n'rn nun rnooriss or MAKING saivi'n.

Patented Jan. 18, 1910.

' The dyestuff thus produced forms a dry,

dark powder which is insolublein water, diluted alkalies and acids,ligroin, alcohol and ether; soluble in concentrated sulfuric acidavith agreenish-blue color; and which dyes, on reduction of the nitro groujp tothe amino-group in the alkaline .hydrosulfite- Vat, cotton and woolviolet-gray to gray tints. By using instead of the thioindigo, para-paradi'chloroortho ortho dimethylthioindigo (S:CI:CH,=1:4::6),, a dyestuffis obtained which dyes cotton in the hydrosulfite vat violet tints,whereas, by starting from the para-para-dichloro-thioindigo (S:Cl=1:4) adyestuii is produced,

- which draws on the fiber also with a violet By halogenizing thenitrated lihlOilktint. digo-dyestuifs thus obtained by means, of bromin,chlorin'or one of the known 'halogen yielcling substances, vat-dyestuffsvare produced which are much .faster and which possess propertiesresembling those of the non-halogenizedproducts.

Y Example II: 20 gr; of the nitr'atedthioindigo dyestufl's, obtainedfrom thioindigo,

para para dichloro ortho ortho dimethylthioindigo. (-S :01 :CH,:: 1 :4:6) ,or para-para.- dichlorothi'oindigo (8131:1241) according to exampleI, are reduced by means of asolution 0 about 10 gr. of crystallizedsodium sulfid in about 70 com. of ater at about filtered and extractedwith boiling water.

The resulting products, when dry, form dark powders which dissolve insulfuric acid monohydrate 'with a greenish color "and dye wool andcotton violet, gray to grayish-black tints, that is to -say,'thereduction-product of the: nitrated thioindigo dyes gray to grayish-blacktints; that of the para-para-di- -chloro ortho orthodilnethylthioindigo(S :61 :GI-I,:1 :4 :6) (a violet powder insoluble in "water, dilutedalkaliesand acids, ligroin, alcohol and ether) dyes violet tints; thatof the para para dichlorothioindigos -(S: Cl: =1:4) dyes violet "hues.These re duced nitrothioindigo-dyestuits also are Icapable of beinghalogenized by meansof bro min, chlo'rin orone of the knownhalogcnyielding substances, whereby vat-dyestuffs of .greater-fastness areobtained.

Having now described our invention, h at we claim is: 1. The process. ofmanufacturingvat-dyestuiis, which consists in nitrating thioindi'go, itshomologues and substitution-products, in absence of Water, 2,. llherocess of manufacturing vat-dyestuds, which consists in nitratingthioindigo, its homologues and substitution products,

reducing the products thus obtained. 3. The process of manufacturingvat-dyestufi's, which consists in nitrating thioindigo, 10 itshomologues and substitutionproducts, and treating the products thusobtained with halogen or'halogen-yielding substances.

4. As new products, the thioin'di 0 dyestuffs obtainable by nitratingthioin igo, its homologues and substitution-products and their productsreduced to amino-bodies, be-

ing violet to dark powders; insoluble in water, diluted alkalies andacids, ligroin,

alcohol and ether; soluble in concentrated sulfuric acid. with agreenish to greenishblue color; yielding when treated wlth alkalinereducing agents, such as hydrosulfite, a vet from which cotton and woolare dyed violet grayish to blackish tints.

5. As a new product, the nitrated and subsequently reduced parit-para-dichloro-ortho- .ort'ho-dimethylthioindigo, being a violet powder;insoluble in water, diluted alkalies and acids, ligroin, alcohol andether; soluble in concentrated sulfuric acid with a green color;-yielding when treated with alkaline reducing agents, such ashydrosu1fite,a vat from which cotton and wool are dyed violet tints.

In testimony whereof, we afiix our signatures in presence oftwowitnesses.

ALBRECHT SCHMIDT. ERNST BRYK.

\Vitnesses JEAN GRUND, CARL GRUND.

